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Discussion Starter · #1 ·
hi all,

i have a 97 323 auto with what i thought was a whining auto box, turns out (after a couple of hrs on the internet looking for an answer) that it is coming through the speakers and is caused by the 'head unit not being grounded' (according to the website i was on anyhow). when i take the front panel off my Sony xrc300rds (think it was fitted at the factory as an option with disk changer in boot.) the noise go's away, when i put it back on, lo and behold the noise is back. the noise is a very high pitched whine that rises and falls with the revs, mainly around 2000-2500 rpm.

does anyone know how to 'ground the head unit' or rectify this problem by other means?

many thanks.
 

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If its a ground problem an interefence suprressors that wires in to the wiring on the back of the alternator may help, we have had to fit one to a truck at work woth 10 spots on the front of his cab that interfere with his radio. You can get them in 12 and 24v.
 

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If its a ground problem an interefence suprressors that wires in to the wiring on the back of the alternator may help, we have had to fit one to a truck at work woth 10 spots on the front of his cab that interfere with his radio. You can get them in 12 and 24v.
I've heard of these but am I correct in saying they don't actually cure the problem, they just hide it?

This is often caused by running power cables, RCA cables too close or crossing over the vehicle loom too often. The whole wiring loom runs down the passenger side from front to back on a 4 and 6 cylinder. Hence the reason the main power cable is sent down the opposite side of the vehicle in the 6 pot:thumbsup

I've heard of tricks such as using tin foil wrapped around stereo/power wiring to shield them.
 

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Just noticed your car spec:hihi

I would put the fault down to the RCA cables. Do you have the thick rubber type or the cheaper clear type?

I always run my RCA's up the centre of the car under the carpet (which is great fun to do):rofl
 

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I've heard of these but am I correct in saying they don't actually cure the problem, they just hide it?

This is often caused by running power cables, RCA cables too close or crossing over the vehicle loom too often. The whole wiring loom runs down the passenger side from front to back on a 4 and 6 cylinder. Hence the reason the main power cable is sent down the opposite side of the vehicle in the 6 pot:thumbsup

I've heard of tricks such as using tin foil wrapped around stereo/power wiring to shield them.
Well yes and no lol. In the instance of the truck it had 10 high power spots with most of the wiring being not far from the head unit so didnt really have much choice in that one as he didnt want to pay to have his cab rewired:thumbsup. If you have got rca cables it might be worth checking them out as A20 said, ideally they are not suppost to be near speaker wires as they can cause interferance same with power cables.
 

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Discussion Starter · #7 ·
ill have to take the radio out to have a look, not sure if ill need some radio pullers or not.

how many of these cables should i be expecting to see? hope this will not involve pulling up any carpet!
 

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I have this same problem, Im putting it down to cowboy wiring & i have 2 lots of pre outs close together. I just havnt found time to work it all out yet.:embarrassed

Good luck, I know how annoying it is
 
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